What an aftermarket remote start system does

An aftermarket remote start is a device that lets you start your car's engine from outside the vehicle using a key fob or smartphone app, without being inside to turn the ignition. The system wires into your car's ignition and starter circuits, then communicates wirelessly with a transmitter you carry. When you press the button, the system triggers the starter motor and fuel pump, and your engine turns over.

This is different from factory remote start, which comes built into some new vehicles at purchase. Aftermarket systems are installed after you own the car, usually by a car alarm shop, car audio installer, or dealership service department. They range from basic key-fob-only models to smartphone-connected systems with GPS tracking and climate control features.

Key Takeaways

  • Aftermarket remote start requires professional installation into your car's electrical system, and the cost typically ranges from $300 to $1,500 depending on the system and your vehicle type.
  • The system must be wired to your ignition, starter, and parking brake circuits, so installation difficulty varies widely — some cars take two hours, others take a full day.
  • Your car's transmission must be in Park (automatic) or Neutral with the parking brake set (manual), or the system will not start the engine as a safety measure.
  • Remote start will not work if your key is in the ignition, your doors are unlocked, or your battery is too weak, and these lockouts exist to prevent theft and accidental engine running.
  • Smartphone-based systems require a cellular connection and a monthly subscription fee, while basic key-fob systems have no ongoing costs after installation.

How the installation process works

Installation begins with the technician running wires from the remote start module (a small computer box) to several circuits in your car: the ignition switch, the starter motor, the parking brake, and the battery. The exact routing depends on your vehicle's year, make, and model — some cars have straightforward wiring that takes a few hours, while others require removing the steering column or dashboard panels, which can take most of a day.

The technician will also program the system to match your car's specific behavior. This includes setting the idle time (how long the engine runs before shutting off if you do not get in), configuring the parking brake sensor, and testing the immobilizer bypass if your car has one. The immobilizer is an anti-theft chip in your key, and some aftermarket systems need to communicate with it so the engine does not shut off when ready after starting.

Once wired and programmed, the technician tests the system multiple times — starting the car from different distances, checking that the engine shuts off when you open a door, and confirming the key fob range. A quality installation shop will also give you a written warranty on the work, usually one to three years.

Cost and what affects the price

A basic aftermarket remote start system costs between $300 and $600 for parts and labor combined. Mid-range systems with smartphone capability run $800 to $1,200. High-end systems with GPS, two-way communication, and advanced climate control can exceed $1,500. These prices assume professional installation at a car alarm shop or dealership.

What you pay depends on three main factors: the system brand and features, your vehicle type, and local labor rates. Luxury cars and trucks with complex electrical systems cost more to install because the wiring is harder to access. Older vehicles sometimes cost less because the wiring is simpler, but some very old cars cannot support remote start at all if the electrical architecture is too different. Labor rates in urban areas are typically higher than in rural areas.

If you choose a smartphone-connected system, budget an additional $10 to $20 per month for the cellular subscription that keeps the system connected to the internet. Some systems bundle the first year of service into the purchase price, so ask about this before you commit.

Safety features that prevent accidental starting

Every aftermarket remote start system includes multiple safety lockouts to prevent the engine from starting when it should not. The most important is the transmission safety switch: on automatic transmissions, the car will only start if it is in Park; on manual transmissions, the parking brake must be set and the clutch pedal must be in the up position. This prevents the car from lurching forward unexpectedly.

The system also will not start if your key is already in the ignition, if any door is unlocked, or if the hood is open. Some systems add a tilt sensor that disables remote start if someone tries to tow the car. If your battery voltage drops too low, the system shuts itself off to avoid draining the battery completely.

Once the engine starts remotely, it will shut off automatically if you do not open a door and get in within a set time — usually five to ten minutes. This prevents the engine from running unattended for hours. When you unlock the car and open the driver's door, the system recognizes your presence and keeps the engine running normally.

Smartphone apps versus key fob only

A key fob system is the simplest and least expensive option. You carry a small remote that looks like a car key, press a button, and the engine starts. The range is typically 500 feet to a quarter mile, depending on the system and local radio interference. Key fob systems have no monthly fees and work even if your phone is dead or out of service.

A smartphone system connects your car to the internet through a cellular modem built into the remote start module. You read an app, log in, and start your car from anywhere — across town, across the country, or across the world. You can also check your car's location, lock and unlock the doors, and set climate control to warm up or cool down the cabin before you arrive. The trade-off is the monthly subscription fee and the requirement that your phone has internet service.

Some systems offer both: a key fob for everyday use and an app for when you want remote access from far away. Smartphone systems also tend to have better diagnostics — they can alert you if the battery is low or if the car has not been started in a week. If you travel frequently or live in a cold climate where warming up the car matters, the app is worth the extra cost. If you mostly want to start the car from your driveway or parking lot, a key fob is sufficient.

Compatibility and vehicle limitations

Most cars made in the last 20 years can have aftermarket remote start installed, but some vehicles present challenges. Cars with push-button start (no traditional ignition switch) require a more complex module that costs more and takes longer to install. Hybrid and electric vehicles have different starting procedures that some aftermarket systems do not support well. Manual transmission cars need a clutch sensor, which adds cost and complexity.

Luxury vehicles with advanced security systems sometimes have immobilizers or anti-theft features that make remote start difficult or impossible without the manufacturer's cooperation. Some high-end cars require dealer-installed systems rather than aftermarket ones. Before you commit to installation, ask the shop whether they have experience with your specific year, make, and model — if they have not installed remote start on that car before, they may underestimate the time and difficulty.

Leased vehicles present a legal issue: most lease agreements prohibit modifications to the electrical system, and installing remote start could violate your lease terms. Check your lease contract or call your leasing company before proceeding. If you own the car outright, you have no restrictions.

Warranty, maintenance, and troubleshooting

A reputable installation shop will warranty the remote start system for one to three years against defects in the module itself. The labor warranty is usually shorter — often one year. This means if the system fails within the warranty period, the shop will repair or replace it at no cost. Read the warranty paperwork carefully to understand what is covered and what is not.

After installation, the system requires almost no maintenance. The key fob battery will need replacement every two to three years, just like a car key fob. If you have a smartphone system, keep the app updated and check your account occasionally to make sure the subscription is active. If the system stops working, the most common causes are a dead key fob battery, a blown fuse in the remote start module, or a loose wire connection — all things the installation shop can diagnose quickly.

If your remote start stops working after a few years, do not assume the whole system is broken. Many problems are straightforward fixes: a corroded battery terminal, a failed relay, or a programming issue. The shop that installed it should be your first call, since they know exactly how it was wired into your car.

Frequently Asked Questions

Will remote start drain my car battery?

No, not under normal use. The system draws very little power when idle, and the engine running for five to ten minutes produces more charge than the remote start consumed. If you start the car remotely every single day without ever driving it, you could eventually drain the battery, but this is rare. Most people use remote start occasionally, and the battery stays healthy.

Can I install remote start myself?

It is technically possible if you have electrical experience and a wiring diagram for your car, but it is not recommended. One wrong wire connection can disable your car's electrical system, trigger the airbags, or create a fire hazard. Professional installation costs $300 to $1,500, which is worth the safety and warranty. If the shop makes a mistake, they fix it for free.

What happens if I lose my key fob?

You can order a replacement from the shop that installed the system or from the system manufacturer. Replacement fobs typically cost $50 to $150. Most shops can program a new fob in minutes. If you have a smartphone system, you can still start your car through the app even if you lose the fob.

Does remote start void my car's warranty?

Not automatically, but it depends on your manufacturer's warranty terms and what goes wrong. If the remote start system causes damage to your car's electrical system, the manufacturer might deny a warranty claim related to that damage. If you have a factory warranty, read it carefully or ask your dealer before installation. Most aftermarket installations do not affect the warranty for unrelated repairs.

Can I use remote start if my car is parked on the street?

Yes, as long as the car is in a safe location and you are not violating local noise ordinances. Some cities have rules about idling or running engines unattended, so check your local regulations. Leaving a car running unattended in a public place also increases theft risk, so use remote start mainly in your driveway or a find parking lot.